As a material of negative electrode of a non-aqueous lithium secondary battery, a lithium metal or lithium alloy has been generally employed. The lithium metal or lithium alloy, however, has a disadvantageous feature in that a lithium metal deposits on the electrode in the branched or tree-like form to give dendrite and produces an internal short circuit or easily ignites due to extremely high activity of the deposited dendrite.
In order to obviate such troubles, a fired carbonaceous material which can reciprocally receive and release lithium ions was developed and has been employed in practice for preparing a negative electrode. This material has a disadvantageous small density and therefore it only gives a relatively low capacity. Further, since the fired carbonaceous material per se has electroconductivity, a lithium metal may deposition the carbonaceous negative electrode in the course of over-charging or rapid charging.
EP-A-615,296 and Japanese Patent Provisional Publications No. H5-174818, No. H6-60867, No. H6-275267, No. H6-325765 and No. H6-338324 disclose that a non-aqueous lithium ion secondary battery showing a high capacity and giving a discharge potential as high as 3 to 3.6 volts can be prepared by the use of an oxide of Sn, V, Si, B or Zr or an oxide of a combination of these metals as the electrode forming-material. In more detail, the negative electrode comprising the oxide of Sn, V, Si, B or Zr, or the oxide of combination of these metals can give a non-aqueous secondary battery which has a discharge potential as high as 3 to 3.6 volts and a large discharge capacity, and produces almost no dendrite under the practically confronting conditions resulting in enhancement of safety.
Journal of Power Sources, 39(1992), 163-178, discloses that highly stable solutions of 1,3-dioxolane with LiClO.sub.4 or LiAsF.sub.6 preferably erployable for secondary lithium batteries may be prepared by the use of tertiary amine derivatives such as trialkylamines such as triethylamine, tripropylamine, tributylamine and trioctylamine and triarylamines such as tribenzylamine, triphenylamine, trimethylpiperidine and trimethylmorpholine.
Japanese Patent Provisional Publication No. H6-333598 discloses that a lithium secondary battery which employs an electrolyte solution containing a trialkylamine or a triarylamine shows good charge-discharge cycle characteristics.